Virgin Media is to begin charging customers wishing to use its London Underground wireless broadband network, it has been reported.
According to ZDNet, the firm will restrict access to Wi-Fi on the Tube "after September".
Created for the London 2012 Olympic and Paralympic Games, the network has been freely available to use over the summer.
But from next month, only Virgin Media's own subscribers will be able to access the web for free on station platforms and in waiting areas.
Other passengers wishing to utilise Wi-Fi on the Tube will be required to sign up and pay for internet access.
Virgin Media is likely to introduce pay-as-you-go tariffs for mobile device users seeking broadband connectivity underground.
Services are already available at more than 80 London stations, with this number set to rise to 120 by the end of 2012.